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Non-destructive prediction of ‘Valencia’ orange ( <i>Citrus sinensis</i> ) and ‘Star Ruby’ grapefruit ( <i>Citrus</i> × <i>paradisi</i> Macfad) internal quality parameters using Vis/NIRS
摘要： Commercial maturity of citrus fruit is measured by sweetness and flavour parameters, which involve the use of destructive, inconsistent, time consuming and expensive techniques such as titrations and destructive refractometer-based juice analysis. New approaches to substitute these techniques involve the application of non-destructive prediction of quality attributes. The ability of visible to near infrared spectroscopy (Vis/NIRS) to non-destructively quantify total soluble solids (TSS), titratable acidity (TA), TSS:TA ratio and BrimA (balance between sugars and acids) of 'Valencia' orange and 'Star Ruby' grapefruit was evaluated. BrimA is an organoleptic parameter considered highly correlated to citrus sweetness and flavour which better aligns with prediction of human perception of good taste. The most accurate model for predicting BrimA was achieved on 'Valencia' orange (R2=0.9576; RMSEP=0.006; RPD=3.96) over 'Star Ruby' grapefruit (R2=0.858; RMSEP=0.429; RPD=2.45). Other parameters were also predicted with high accuracy. This study demonstrated the ability of Vis/NIRS, combined with chemometrics, to non-destructively predict sweetness and flavour attributes of oranges and grapefruit. Commercial application of NIRS models for predicting citrus fruit internal quality parameters prior to pricing of fruit was suggested as a tool for increasing reliability between suppliers and consumers.
关键词： citrus flavour,BrimA,maturity index,near infrared spectroscopy
更新于2025-09-19 17:15:36
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In-line near infrared spectroscopy for the prediction of moisture content in the tapioca starch drying process
摘要： Moisture content is an important parameter measured in tapioca starch production as this parameter has been shown to correlate strongly with the quality of the ?nished product. However, there is currently no in-line sensor which can be used to directly measure the moisture content of the product in real time. The objective of the present work was to study the use of an in-line measurement which can be introduced at the end of the drying process for tapioca starch moisture content evaluation. Either in-line NIR data or at-line NIR data was used to develop the necessary calibration models for evaluating the moisture content. Furthermore, calibration models were also developed by pooling the in-line and at-line data. Its performance was then veri?ed using additional in-line data. The NIR model developed using 100% of the at-line data and 50% of the in-line data was validated using the unused 50% of the inline data. This model was shown to provide better performance in moisture content prediction with an SEP of 0.61% and a bias of 0.001%. In addition, the results showed that the at-line spectrum can also be used for the calibration model development to predict the moisture content of the samples scanned by an in-line spectrometer. However, the in-line spectrometer installation on a pneumatic conveying circular tube where tapioca starch and air mixed was found to be complicated due to signi?cant vibration. This caused additional variation in the data with time. Therefore, it is concluded that the most suitable place for installing a spectrometer would be at a position involving a low pressure, or where the stream ?ow of a product is steadier in order to avoid the dynamic mixing of the product within the drying tube affecting the uncertainty of NIR scattering during the measurement.
关键词： Moisture content,Tapioca starch,Drying process,In-line near infrared spectroscopy
更新于2025-09-19 17:15:36
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Aging effects on prefrontal cortex oxygenation in a posture-cognition dual-task: an fNIRS pilot study
摘要： Background: The aging process alters upright posture and locomotion control from an automatically processed to a more cortically controlled one. The present study investigated a postural-cognitive dual-task paradigm in young and older adults using functional Near-Infrared Spectroscopy (fNIRS). Methods: Twenty healthy participants (10 older adults 72 ± 3 y, 10 young adults 23 ± 3 y) performed a cognitive (serial subtractions) and a postural task (tandem stance) as single-tasks (ST) and concurrently as a dual-task (DT) while the oxygenation levels of the dorsolateral prefrontal cortex (DLPFC) were measured. Results: In the cognitive task, young adults performed better than older adults in both conditions (ST and DT) and could further increase the number of correct answers from ST to DT (all ps ≤ 0.027) while no change was found for older adults. No significant effects were found for the postural performance. Cerebral oxygenation values (O2Hb) increased significantly from baseline to the postural ST (p = 0.033), and from baseline to the DT (p = 0.031) whereas no changes were found in deoxygenated hemoglobin (HHb). Finally, the perceived exertion differed between all conditions (p ≤ 0.003) except for the postural ST and the DT (p = 0.204). Conclusions: There was a general lack of age-related changes except the better cognitive performance under motor-cognitive conditions in young compared to older adults. However, the current results point out that DLPFC is influenced more strongly by postural than cognitive load. Future studies should assess the different modalities of cognitive as well as postural load.
关键词： Attention,Functional near-infrared spectroscopy (fNIRS),Postural control,Aging,Dual-tasking,Executive control,Balance,Elderly
更新于2025-09-19 17:15:36
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Conducting Hyperscanning Experiments with Functional Near-Infrared Spectroscopy
摘要： Concurrent brain recordings of two or more interacting persons, an approach termed hyperscanning, are gaining increasing importance for our understanding of the neurobiological underpinnings of social interactions, and possibly interpersonal relationships. Functional near-infrared spectroscopy (fNIRS) is well suited for conducting hyperscanning experiments because it measures local hemodynamic effects with a high sampling rate and, importantly, it can be applied in natural settings, not requiring strict motion restrictions. In this article, we present a protocol for conducting fNIRS hyperscanning experiments with parent-child dyads and for analyzing brain-to-brain synchrony. Furthermore, we discuss critical issues and future directions, regarding the experimental design, spatial registration of the fNIRS channels, physiological influences and data analysis methods. The described protocol is not specific to parent-child dyads, but can be applied to a variety of different dyadic constellations, such as adult strangers, romantic partners or siblings. To conclude, fNIRS hyperscanning has the potential to yield new insights into the dynamics of the ongoing social interaction, which possibly go beyond what can be studied by examining the activities of individual brains.
关键词： neuroscience,brain-to-brain synchrony,cooperation,fNIRS,parent-child interaction,hyperscanning,functional near-infrared spectroscopy
更新于2025-09-19 17:15:36
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Maintaining the predictive abilities of egg freshness models on new variety based on VIS-NIR spectroscopy technique
摘要： This research was performed to study calibration model transfer between White Leghorns eggs and Bantam eggs for prediction of egg freshness by visible near infrared (VIS-NIR) spectroscopy. Transmission spectra of the two varieties were acquired in the equatorial region of the eggs. And albumen pH as the freshness evaluating parameter was measured using traditional destructive methods. After outliers were eliminated by Mahalanobis distance combined with principal component analysis (PCA), partial least squares regression (PLSR) with different preprocessing methods was used to develop prediction models. Global updating, direct standardization (DS) and slope/bias correction (SBC) were evaluated to transfer calibration models from one variety to another. The Kennard-Stone (KS) algorithm was used to select standardization samples. White Leghorns eggs and Bantam eggs as the master variety in turn were compared to find superior master variety. Application of the slope/bias correction (SBC) algorithm obtained the best prediction results of albumen pH. And the better slope/bias correction (SBC) transfer performance with a rp of 0.908 and a RMSEP of 0.133 was found when Bantam eggs were as the superior master variety.
关键词： Slope/bias correction,Visible near infrared spectroscopy,Direct standardization,Global updating,Egg
更新于2025-09-19 17:15:36
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Application of infrared spectroscopy as Process Analytics Technology (PAT) approach in biodiesel production process utilizing Multivariate Curve Resolution Alternative Least Square (MCR-ALS)
摘要： Process Analytical Technology means at-line collection of analytical information from the process when the reaction is in progress. Obtained information enables process engineers to better control the Critical Process Parameters and direct the reaction to desirable routs. Near-infrared spectroscopy due to its analytical features, as well as the high capability of automation, versatile sampling and spectral acquisition methods is a useful tool in process monitoring when coupled to chemometrics. The Multiple Scatter Correction preprocessing technique and Alternative Least Square method can extract spectral and concentration information of a reaction mixture simultaneously, were employed pairing with fiber optic Near-Infrared spectroscopy in 1000-2250 nm spectral region was employed to extract the analytical information from the biodiesel production process. The obtained output demonstrated appropriate results about the concentration and type of components during the process. The kinetics of the reaction was also studied using the obtained results and showed a three-stage kinetics with different rates.
关键词： MCR-ALS,Near-Infrared spectroscopy,Process Analytical Technology,Biodiesel
更新于2025-09-19 17:15:36
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EXPRESS: Use of Visible–Near-Infrared (Vis–NIR) Spectroscopy to Detect Aflatoxin B <sub/>1</sub> on Peanut Kernels
摘要： Current methods for detecting aflatoxin contamination of agricultural and food commodities are generally based on wet chemical analyses, which are time-consuming, destructive to test samples and require skilled personnel to perform, making them impossible for large-scale nondestructive screening and on-site detection. In this study, we utilized visible–near-infrared (Vis–NIR) spectroscopy over the spectral range of 400–2500 nm to detect contamination of commercial, shelled peanut kernels (runner type) with the predominant aflatoxin B1 (AFB1). The artificially contaminated samples were prepared by dropping known amounts of aflatoxin standard dissolved in methanol, onto peanut kernel surface to achieve different contamination levels. The partial least squares discriminant analysis (PLS-DA) models established using the full spectra over different ranges achieved good prediction results. The best overall accuracy of 88.57% and 92.86% were obtained using the full spectra when taking 20 and 100 parts per billion (ppb), respectively, as the classification threshold. The random frog (RF) algorithm was used to find the optimal characteristic wavelengths for identifying the surface AFB1-contamination of peanut kernels. Using the optimal spectral variables determined by the RF algorithm, the simplified RF-PLS-DA classification models were established. The better RF-PLS-DA models attained the overall accuracies of 90.00% and 94.29% with the 20 ppb and 100 ppb thresholds, respectively, which were improved compared to using the full spectral variables. Compared to using the full spectral variables, the employed spectral variables of the simplified RF-PLS-DA models were decreased by at least 94.82%. The present study demonstrated that the Vis–NIR spectroscopic technique combined with appropriate chemometric methods could be useful in identifying AFB1 contamination of peanut kernels.
关键词： Vis–NIR,PLS-DA,peanut kernel,visible–near-infrared spectroscopy,random frog,Aflatoxin,partial least squares discriminant analysis
更新于2025-09-19 17:15:36
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A feasibility study on quantitative analysis of low concentration methanol by FT-NIR spectroscopy and aquaphotomics
摘要： Methanol content is a key parameter in the fermentation industry. However, the methanol concentration during fermentation is usually quite low, it's necessary to find a method to measure methanol with low content, even indirectly. Near infrared spectroscopy (NIRS) technology is rapid and non-destructive, which can provide analytical solutions for components that represent approximately 1%. Aquaphotomics gives the chance to dig into the information remaining hidden in the NIR spectra, which shows a distinct advantage if the target object is presented in lower concentrations. Therefore, NIRS combined with aquaphotomics was introduced in this study to prove the feasibility for methanol determination at 0.1%-2.5% (v/v) in aqueous solutions. Determination coefficient of calibration (R2 c), validation (R2 cv), root mean square error of calibration (RMSEC), validation (RMSEP) and cross validation (RMSECV) were applied to verify the performance of the partial least squares regression (PLSR) models, and the corresponding values of best model were 0.999, 0.999, 1.000, 0.0204%, 0.0277%, 0.0142%, respectively. Our successfully result indicated that NIRS technique combined with aquaphotomics may open a new perspective in methanol determination.
关键词： Aquaphotomics,Low concentration,Methanol,Near infrared spectroscopy
更新于2025-09-19 17:15:36
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Wearable-band Type Visible-Near Infrared Optical Biosensor for Non-invasive Blood Glucose Monitoring
摘要： Diabetes is a worldwide-serious problem that can only be delayed or prevented by a regular monitoring of blood glucose (BG) concentration level. Continuous monitoring systems allow subjects to prepare the diabetes management strategy and prevent the long-term complications diseases. Until now, most studies utilize various biofluids such as sweat, tears and saliva that have serious unresolved setback such as expensive material, sensor stability, sensor calibration and long-settling time. Therefore, we developed a novel BG sensor which is cost efficient and highly wearable with a small data acquisition time window that allow a non-invasive, long-term continuous blood glucose monitoring (CGM) system. The novel biosensor exploits a unique information of the pulsatile to continuous components of the arterial blood volume pulsation during the change of blood glucose (BG) concentration at the wrist tissue. The reflected optical signal was measured in the combine visible-near infrared (Vis-NIR) spectroscopy. An in-vivo experiment which enclosed 12 volunteers in a two-hour modified carbohydrate-rich meals reached the average correlation coefficient (????) between the estimated and reference BG concentration of 0.86, with the standard prediction error (SPE) of 6.16 mg/dl. Moreover, the full-day experiment was also conducted to test the reliability of the proposed sensor. Results showed that the created model in the previous day, may estimate a full-day BG concentration which was done in next day with an adequate performance.
关键词： Wearable Sensor,Optical Biosensor,Noninvasive Measurement,Visible-Near Infrared Spectroscopy,Diabetes,Continuous Blood Glucose Monitoring
更新于2025-09-19 17:15:36
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Intravascular Molecular Imaging to Detect High-Risk Vulnerable Plaques: Current Knowledge and Future Perspectives
摘要： Purpose of Review To describe vulnerable plaque pathobiology and summarize potential targets for molecular imaging with a focus on intravascular near-infrared fluorescence (NIRF) and its translatable applications. Recent Findings Structural imaging alone is unable to precisely identify high-risk plaques in patients with coronary artery disease (CAD). Intravascular near-infrared fluorescence (NIRF) imaging is an emerging translational approach that can image specific in vivo molecular processes and cells that characterize vulnerable plaques. High-priority NIRF targets imaged by intravascular NIRF imaging thus far include macrophages, cathepsin protease activity, oxidized low-density lipoprotein (oxLDL), and abnormal endothelial permeability. The newest generation of NIRF catheters is multimodal in nature and combines NIRF with either IVUS or OCT, providing simultaneous co-registered morphological and pathobiological assessment of atherosclerotic plaques. While most intravascular NIRF studies have been performed in a preclinical environment, a first-in-human NIR autofluorescence-OCT trial has recently been performed. These developments suggest that clinical intravascular NIRF molecular imaging will be available within the next 3 years. Summary Molecular imaging is a powerful approach to enhance our understanding of atherosclerosis pathophysiology. Intravascular NIRF/OCT and NIRF/IVUS molecular imaging is nearing its use in atherosclerosis patients and will initially leverage indocyanine green (ICG) as an FDA-approved NIRF agent that reports on abnormal plaque permeability. Clinical trials are needed to assess the value of intravascular NIRF imaging using ICG as well as other novel NIRF imaging agents to better understand vulnerable plaque pathobiology, event prediction, and to enable personalized pharmacotherapy of high-risk plaques and patients.
关键词： Molecular imaging,Vulnerable plaque,Near-infrared spectroscopy,OCT,Atherosclerosis,Near-infrared fluorescence,IVUS
更新于2025-09-19 17:13:59